Feature/video queue (#23)

* Added VideoQueue Control
* Added VideoQueue Example
* Added Additional Attributes bag support
* Added conditional render for additional attributes
* Fixed NREX with Additional Attributes
* Added Play method for direct playback of a single VideoSource
* Added warning ignores
* Added additional check that no prior event is overwritten
* Updated comment for delay clarification
* Added additional event types
* Added Extensive exception information
* Updated Example property access
* Updated Example
* Updated Readme

---------

Co-authored-by: JPVenson <[email protected]>

README.md

@@ -9,6 +9,7 @@ The easiest html5 `video` implementation for [Blazor](https://blazor.net) applic
 ![Screenshot of the component in action](screenshot.png)
 
 ## Changelog
+
 ### 2022-24-12 Version 1.1
  - Bump dotnet version to 6.0 as 3.x and 5.x are now out of support.
  - Add standard Methods and Properties (big thanks to https://github.com/JPVenson) and Async versions (for Server/WASM). (Issues #17 #9)
@@ -243,6 +244,66 @@ _Note: Attempting to read/write Properties from Blazor Server will throw a runti
 Example - Remote JS (Server) and WASM
 `int duration = await videoRef.GetDurationAsync()`
 
+## Video Queue
+> Hint: When using the `VideoQueue` component, the `BlazoredVideo.EndedEvent` is unavailable as it is utilized by the `VideoQueue`. You must instead use the `VideoQueue.OnNextPlayed` or `OnNextPlayed.OnPlaylistEnded` events.
+
+By using the `<VideoQueue>` component instead of setting your `<source />` directly you can create a queue of videos that will be played sequentially. The VideoQueue supports multiple versions of each source and can be set to different repeat behaviors:
+
+Example Simple queue
+```razor
+<BlazoredVideo>
+     <VideoQueue Delay="0" Repeat="No">
+        <VideoItem Source="videos/elephants.mp4" type="video/mp4" />     
+        <VideoItem Source="videos/chimpanese.mp4" type="video/mp4" />     
+        <VideoItem Source="videos/turtles.mp4" type="video/mp4" />     
+     </VideoQueue>
+</BlazoredVideo>
+```
+The simple queue will play all 3 videos after each other and then stop. It is possible to control the repeat behavior by setting the Repeat property. 
+
+| Repeat | Description 
+| --- | --- | 
+| NoLoop | Plays all videos in order and stops after the last one 
+| LoopOne | Repeats the current video forever 
+| LoopAll | Starts at the beginning of the queue after the last video was played 
+
+It is also possible to control the VideoQueue directly by obtaining the VideoQueue reference and invoking ether `PlayNext` or `PlayPrevious` like this:
+```razor
+<BlazoredVideo>
+     <VideoQueue @ref="videoQueue">
+        <VideoItem Source="videos/elephants.mp4" type="video/mp4" />     
+        <VideoItem Source="videos/chimpanese.mp4" type="video/mp4" />     
+        <VideoItem Source="videos/turtles.mp4" type="video/mp4" />     
+     </VideoQueue>
+</BlazoredVideo>
+
+
+<div class="d-flex flex-row">
+	<button @onclick="() => videoQueue.PlayNext()">Next</button>
+	<button @onclick="() => videoQueue.PlayPrevious()">Previous</button>
+</div>
+
+@code
+{
+	VideoQueue videoQueue;
+}
+
+```
+
+To provide multiple versions of your video you can create a `VideoSource` under each `VideoItem`.
+```razor
+<BlazoredVideo>
+     <VideoQueue @ref="videoQueue">
+        <VideoItem>
+           <VideoSource Source="videos/elephants.mp4" type="video/mp4" />
+           <VideoSource Source="videos/elephants.ogg" type="video/ogg" />
+        </VideoItem>
+        <VideoItem Source="videos/chimpanese.mp4" type="video/mp4" />     
+        <VideoItem Source="videos/turtles.mp4" type="video/mp4" />     
+     </VideoQueue>
+</BlazoredVideo>
+```
+
 ### Customising the html
 
 The Video can be customised using standard CSS techniques. 

samples/SharedRCL/Pages/QueueItems.razor

@@ -0,0 +1,82 @@
+@page "/queue"
+
+<h1>Blazored Video Demo - Queue</h1>
+
+<div class="d-flex flex-row">
+	<BlazoredVideo class="w-40"
+	               autoplay="autoplay"
+	               style="max-width: 300px;">
+		<VideoQueue @ref="videoQueue" 
+		            OnNextPlayedEvent="StateHasChanged" 
+		            OnPlaylistEndedEvent="StateHasChanged"
+		            Delay="Delay"
+		            Repeat="Repeat">
+			<VideoItem Source="video/elephants2.mp4#t=3" Type="video/mp4"/>
+			<VideoItem>
+				<VideoSource Source="http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4" Type="video/mp4" />
+			</VideoItem>
+			<VideoItem Source="http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/ElephantsDream.mp4" Type="video/mp4" />
+			<VideoItem Source="http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/VolkswagenGTIReview.mp4" Type="video/mp4" />
+		</VideoQueue>
+	</BlazoredVideo>
+
+
+	@if (videoQueue != null)
+	{
+		<div class="list-group">
+			@foreach (var videos in videoQueue.VideoItems)
+			{
+				<div class="list-group-item selectable @((videos == videoQueue.CurrentItem ? "list-group-item-info" : ""))"
+				     @onclick="() => videoQueue.Play(videos)">
+					<span>@(videos.VideoSourceData.First().Source.Split('/').Last())</span>
+				</div>
+			}
+		</div>
+	}
+
+</div>
+
+
+<div class="d-flex flex-row">
+	<button @onclick="() => videoQueue.PlayNext()">Next</button>
+	<button @onclick="() => videoQueue.PlayPrevious()">Previous</button>
+</div>
+
+<br/>
+<EditForm Model="this">
+	<div class="form-group">
+		<label for="repeat">Repeat: </label>
+
+		<InputSelect @bind-Value="Repeat" id="repeat">
+			@foreach (var repeatVal in Enum.GetValues(typeof(RepeatValues)))
+			{
+				<option value="@repeatVal">@repeatVal</option>
+			}
+		</InputSelect>
+	</div>
+	<div class="form-group">
+		<label for="repeat">Delay: </label>
+		<InputNumber @bind-Value="Delay" id="delay"/>
+	</div>
+</EditForm>
+
+@code
+{
+	VideoQueue videoQueue;
+
+	public RepeatValues Repeat { get; set; }
+	public int Delay { get; set; }
+
+	protected override void OnAfterRender(bool firstRender)
+	{
+		if (firstRender)
+		{
+			SetupDisplay();
+		}
+	}
+
+	private void SetupDisplay()
+	{
+		StateHasChanged();
+	}
+}

samples/SharedRCL/Shared/NavMenu.razor

@@ -42,6 +42,11 @@
 				<span class="oi oi-plus" aria-hidden="true"></span> Multiple Videos
 			</NavLink>
 		</li>
+		<li class="nav-item px-3">
+			<NavLink class="nav-link" href="queue">
+				<span class="oi oi-plus" aria-hidden="true"></span> Queueing
+			</NavLink>
+		</li>
 	</ul>
 </div>
 

src/Blazored.Video/BlazoredVideo.razor

@@ -19,4 +19,6 @@
 		}
 	}
 *@
-<video id="@UniqueKey" @key="UniqueKey" @attributes=@Attributes @onchange=@OnChange @ref="videoRef">@ChildContent</video>
+<CascadingValue Value="this">
+<video id="@UniqueKey" @key="UniqueKey" @attributes=@Attributes @onchange=@OnChange @ref="videoRef">@ChildContent</video>
+</CascadingValue>

src/Blazored.Video/BlazoredVideo.razor.cs

@@ -178,11 +178,11 @@ async Task Implement(VideoEvents eventName)
 			{
 				await jsModule.InvokeVoidAsync("registerCustomEventHandler", videoRef, eventName.ToString().ToLower(), options.GetPayload());
 			}
-      catch (Exception ex)
-      {
+			catch (Exception ex)
+			{
 				LoggerFactory
 					.CreateLogger(nameof(BlazoredVideo))
-          .LogError(ex, "Failed to register an event handler for {0}", eventName);
+					.LogError(ex, "Failed to register an event handler for {0}", eventName);
 			}
 		}
 
@@ -199,6 +199,7 @@ protected virtual void OnChange(ChangeEventArgs args)
 			{
 				videoData = JsonSerializer.Deserialize<VideoEventData>(ThisEvent, serializationOptions);
 				videoData.Video = this;
+				videoData.State ??= new VideoState();
 				videoData.State.Video = this;
 			}
 			catch (Exception ex)
@@ -304,6 +305,7 @@ protected virtual void OnChange(ChangeEventArgs args)
 			// Here is our catch-all event handler call!
 			EventFired?.Invoke(videoData);
 		}
+
 		bool RegisterEventFired => EventFiredEventRequired || EventFiredRequired;
 		bool RegisterAbort => AbortEventRequired || AbortRequired;
 		bool RegisterCanPlay => CanPlayEventRequired || CanPlayRequired;

src/Blazored.Video/RepeatValues.cs

@@ -0,0 +1,22 @@
+namespace Blazored.Video;
+
+/// <summary>
+///		Defines methods for a <see cref="VideoQueue"/> to behave when a video source was played to its end.
+/// </summary>
+public enum RepeatValues
+{
+	/// <summary>
+	///		Defines no repetition after the queue reached its end.
+	/// </summary>
+	NoLoop,
+
+	/// <summary>
+	///		Will repeat the current loaded video forever.
+	/// </summary>
+	LoopOne,
+
+	/// <summary>
+	///		Loops back to the first video after the last one ended.
+	/// </summary>
+	LoopAll
+}

src/Blazored.Video/VideoItem.cs

@@ -0,0 +1,69 @@
+using System;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.Rendering;
+
+namespace Blazored.Video;
+
+/// <summary>
+///		Defines a Source from which the <see cref="VideoQueue"/> will schedule playback.
+/// </summary>
+public sealed class VideoItem : ComponentBase, IDisposable
+{
+	public VideoItem()
+	{
+		VideoItemData = new VideoItemData();
+	}
+
+	/// <summary>
+	///		The source URI from which to playback.
+	/// </summary>
+	[Parameter]
+	public string Source { get; set; }
+
+	/// <summary>
+	///		The mime type of the <see cref="Source"/> URI. Optional.
+	/// </summary>
+	[Parameter]
+	public string Type { get; set; }
+
+	[CascadingParameter()]
+	public VideoQueue VideoQueue { get; set; }
+
+	[Parameter]
+	public RenderFragment ChildContent { get; set; }
+
+	public VideoItemData VideoItemData { get; set; }
+
+	protected override void BuildRenderTree(RenderTreeBuilder builder)
+	{
+		if (ChildContent == null)
+		{
+			return;
+		}
+
+		builder.OpenComponent<CascadingValue<VideoItem>>(0);
+		builder.AddAttribute(1, nameof(CascadingValue<VideoItem>.Value), this);
+		builder.AddAttribute(2, nameof(CascadingValue<VideoItem>.IsFixed), true);
+		builder.AddAttribute(3, nameof(CascadingValue<VideoItem>.ChildContent), (RenderFragment)((cBuilder) =>
+		{
+			cBuilder.AddContent(4, ChildContent);
+		}));
+		builder.CloseComponent();
+	}
+
+	protected override void OnInitialized()
+	{
+		if (!string.IsNullOrWhiteSpace(Source))
+		{
+			VideoItemData.VideoSourceData.Add(new VideoSourceData(Source, Type));
+		}
+
+		VideoQueue.AddVideoItem(VideoItemData);
+	}
+
+	public void Dispose()
+	{
+		VideoQueue.VideoItems.Remove(VideoItemData);
+	}
+}

src/Blazored.Video/VideoItemData.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+
+namespace Blazored.Video;
+
+/// <summary>
+///		Contains the list of sources to be played back by a <see cref="VideoQueue"/>.
+/// </summary>
+public class VideoItemData
+{
+	public VideoItemData()
+	{
+		VideoSourceData = new List<VideoSourceData>();
+		Id = Guid.NewGuid().ToString("N");
+	}
+
+	internal string Id { get; }
+
+	/// <summary>
+	///		The <see cref="VideoSourceData"/> that can be used to playback a source.
+	/// </summary>
+	public IList<VideoSourceData> VideoSourceData { get; set; }
+}